This type of information recording apparatus is constructed to record information by laser light for recording with a pulse width, pulse intensity, a pulse shape, recording strategy, or the like which are preferable (referred to as a “preferable irradiation condition” in this application as occasion demands) in accordance with the recording layer of the information recording medium, such as an optical disc.
Here, as described in a patent document 1 or the like, there is also developed an information recording medium, such as a multiple layer or multilayer type, or dual layer type optical disc, in which a plurality of recording layers are stacked or laminated on the same substrate. The information recording apparatus firstly performs the recording with respect to a recording layer located on the top, and secondly performs the recording with respect to a recording layer located on the second top, in the preferable irradiation condition defined for such a multilayer type information recording medium.    Patent document 1: Japanese Patent Application Laying Open NO. 2000-311346